One of the most common customizations to KnowledgeLake software is to customize the act of Indexing, or applying metadata to SharePoint documents. While KnowledgeLake software has always made these customizations possible, it has never been easier than with the newly redesigned Index component built into KnowledgeLake Imaging 4.0.

In this post, I will walk through how to create a very basic KnowledgeLake Index extension that will load a special default value into a DueDate column. This extension can easily be deployed for farm-wide use in the KnowledgeLake Imaging Index Edit Form, the KnowledgeLake Viewer, the KnowledgeLake Search Query Results Web Part and the KnowledgeLake Search Query Results built into the KnowledgeLake Search Center. This post assumes you have some existing Knowledge of programming with Visual Studio and some general, high level Knowledge of how the KnowledgeLake Index Behaviors integrate with SharePoint 2010's Content Types.

Step 1: Creating the extension

In order to create extensions for KnowledgeLake Index, you will need the following tools and Silverlight assemblies. Additionally, I will assume you are developing on your SharePoint server. This has become easier than ever since SharePoint 2010 can now be deployed on Windows 7!

• Microsoft Visual Studio 2010
• The Silverlight 4 developer runtime and tools for Visual Studio 2010.
• The Microsoft SharePoint Silverlight Client Object assemblies.
  • Microsoft.SharePoint.Client.Silverlight
  • Microsoft.SharePoint.Client.Silverlight.Runtime
  • System.Windows.Controls
• The KnowledgeLake Imaging Silverlight assemblies (found in the KnowledgeLake Imaging SDK or can be extracted from the KLViewer2.xap or KLEditForm.xap packages.
  • KnowledgeLake.Silverlight
  • KnowledgeLake.Silverlight.Index.Client
  • KnowledgeLake.Silverlight.Index.Contracts
  • KnowledgeLake.Silverlight.Index.Controls (optional)

Start by creating a new Silverlight application project in Visual Studio. This will allow generation of a xap project to deploy to the SharePoint farm. The KnowledgeLake Index component is expecting the xap package to be titled KLIndexExtensions, so call it that. Additionally, add references to all of the assemblies listed above to your project.

Create a new ResourceDictionary in your project and call it CustomTemplates.xaml.  For the purpose of being able to instantiate this class in code behind, add a CustomTemplates.cs class alongside of it.  This is where the meat of the extension will lie.  Add the code shown below into your CustomTemplates.xaml. 

<ResourceDictionary x:Class="KLIndexExtensions.Resources.CustomTemplates"
                    x:ClassModifier="public"
                    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:System_Windows_Controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls"
                    xmlns:converters="clr-namespace:KLIndexExtensions.Converters;assembly=KLIndexExtensions"                                       
                    xmlns:KnowledgeLake_Silverlight_Index_Controls=

			"clr-namespace:KnowledgeLake.Silverlight.Index.Controls;assembly=KnowledgeLake.Silverlight.Index.Controls">
    <KnowledgeLake_Silverlight_Index_Controls:IndexColumnTemplate x:Key="CustomDateTemplate" 
                  ColumnDataTypes="DateTime" Modes="Index, Modify" DisplayFormats="DateOnly">        
        <StackPanel>
            <System_Windows_Controls:DatePicker 

		SelectedDate="{Binding Value, Mode=TwoWay}" 

		Loaded="OnDatePickerLoaded" />
        </StackPanel>        
    </KnowledgeLake_Silverlight_Index_Controls:IndexColumnTemplate>
</ResourceDictionary>

Next, we will go back to our CustomIndexPanelTemplateLoader.cs file and return a new instance of the CustomTemplates ResourceDictionary as shown (note that I decided to add my CustomTemplates ResourceDictionary to a Resources namespace within my application).

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using KnowledgeLake.Silverlight.Index.Contracts;
 
namespace KLIndexExtensions
{
    public class CustomIndexPanelTemplateLoader : IIndexPanelTemplateLoader
    {
        public ResourceDictionary LoadTemplates()
        {
            return new KLIndexExtensions.Resources.CustomTemplates();
        }
    }
}

Finally, add the code shown below to your CustomTemplates.cs.   The OnDatePickerLoaded event handler will handle anytime a column named “DueDate” is loaded without an existing value, the value will be populated with the first day of the following month.  Build the project, which will create KLIndexExtensions.xap.  This is the package that is deployed to the SharePoint farm for use with KnowledgeLake products.

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using KnowledgeLake.Silverlight.Index.Controls.ViewModel;

namespace KLIndexExtensions.Resources
{
    public partial class CustomTemplates
    {
        public CustomTemplates() 
        {
            InitializeComponent();
        }

        private void OnDatePickerLoaded(object sender, EventArgs e)
        {
            DatePicker dp = sender as DatePicker;
            ColumnModel model = dp.DataContext as ColumnModel;

            if (model.DisplayName == "DueDate" && string.IsNullOrEmpty(model.Value))
            {
                DateTime dueDate = DateTime.Now.AddMonths(1);
                dueDate = new DateTime(dueDate.Year, dueDate.Month, 1);
                model.Value = dueDate.ToString("o");
            }
        }
    }
}

Step 2:  Deploying your extension xap package

In order for KnowledgeLake Index enabled products to use this extension, it needs to be deployed to 2 different directories on every web front end server in the farm.  Deploy it to the following location to enable it for use in the KnowledgeLake Index Edit Form and KnowledgeLake Search.

·         %SHAREPOINT_ROOT%\TEMPLATE\LAYOUTS\KLClientBin

Secondly, it must be deployed to a subdirectory of the KnowledgeLake Viewer to enable the extension in KnowledgeLake View.  This is because the Viewer resides in its own IIS application.

·         %SHAREPOINT_ROOT%\TEMPLATE\LAYOUTS\KLViewer\ClientBin

Note that the default location of %SHAREPOINT_ROOT% is “C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14”.  That’s it!  Your extension will now be picked up by KnowledgeLake products across your entire farm!

Step 2: Deploying your extension xap package

In order for KnowledgeLake Index enabled products to use this extension, it needs to be deployed to 2 different directories on every web front end server in the farm. Deploy it to the following location to enable it for use in the KnowledgeLake Index Edit Form and KnowledgeLake Search.

• %SHAREPOINT_ROOT%\TEMPLATE\LAYOUTS\KLClientBin

Secondly, it must be deployed to a subdirectory of the KnowledgeLake Viewer to enable the extension in KnowledgeLake View. This is because the Viewer resides in its own IIS application.

• %SHAREPOINT_ROOT%\TEMPLATE\LAYOUTS\KLViewer\ClientBin

Note that the default location of %SHAREPOINT_ROOT% is "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14". That's it! Your extension will now be picked up by KnowledgeLake products across your entire farm!

Step 3: Debugging

If only every extension were that easy! Inevitably, you'll want to be able to step into the extension code as you develop your extension. While there are many ways to accomplish this, I will show you a way I found easiest when developing extensions. Start by going to the properties page for your KLIndexExtensions.Web project created by the Visual Studio Wizard earlier. In the Web tab, choose a valid url where your extension will be hosted. I've chosen the KnowledgeLake Viewer here.

Under debuggers, select Silverlight and unselect ASP.NET.

Simply hit F5 and you will be able to set breakpoints and step into your code. I like to set up post build events to copy my xap to the destination directories on my development server, but make sure you remove them as needed for your team.

Summary

There are many ways to extend KnowledgeLake Index, and KnowledgeLake Index for Imaging 4 makes it easier than ever before. While deployment can be as simple as a copy operation, you could create a custom wsp solution for a multi WFE environment. For more information on creating wsp's, see this MSDN article. For more complex Index scenarios and more development scenarios, please see the KnowledgeLake Imaging SDK, which will be available at the end of this month.